Date: Sun, 27 Oct 2002 09:37:23 -0800 (PST) From: David Nicholas Kayal <davek@saturn5.com> To: nbari@unixmexico.com Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: i am looking for a 5 volt signal Message-ID: <Pine.BSF.4.44.0210270935540.398-100000@blackbox.yayproductions.com> In-Reply-To: <34470.148.243.211.1.1035740270.squirrel@mail.unixmexico.net>
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I'm having problems just using 1 bit fromt he parallel port at this time. On Sun, 27 Oct 2002 nbari@unixmexico.com wrote: > the parallel port then is ok > now you can use a logical multiplexer > > and from the paralel port you can use just 3 bits > > take a look to the data sheets ot this multiplexer > > http://www.cs.utah.edu/classes/cs3700/handouts/pdf/MM74C150.pdf > > the input of the multiplexer will be > > 000 > 001 > 010 > 011 > 100 > 101 > 110 > 111 > > and at the ouput you will have a leched 1 or 0 ( 5volts or 0 volts) the > ones you can aply to your relays > > > > Shouldn't the fact that the signal is in a while loop keep the 5 volt > > signal going? Isn't the parallel port being blasted with the > > value 255 over and over again? > > > > The serial port will not fulfill what i am ultimately trying to achive. > > I am trying to have the parallel port to control 8 relays each turing > > on/off based upon which bit i send out to the port. > > > > On Sun, 27 Oct 2002 nbari@unixmexico.com wrote: > > > >> try using also the serial port and a logical buffer > >> > >> the 5 volt signal is very fast and your multimeter is maybe not to > >> fast > >> > >> > I'm looking for a 5 volt signal. > >> > > >> > I have wires plugged into pins 2 and 25 of the parallel port. > >> > > >> > I have written a small program: > >> > > >> > #include <stdio.h> > >> > #include <dev/ppbus/ppi.h> > >> > #include <dev/ppbus/ppbconf.h> > >> > > >> > int main() > >> > { > >> > int fd; > >> > while(1) > >> > { > >> > ioctl(fd, PPISDATA, 255); > >> > } > >> > } > >> > > >> > and have it executing... > >> > > >> > I have a multi-meter with the positive lead touching the pin 2 wire > >> and the negative lead touching pin 25 wire, but i am not registering > >> any voltage. > >> > > >> > =3D( > >> > > >> > I am sad. > >> > > >> > I have recompiled my kernel to disable plip and enable ppi. The > >> following is a snipet of my kernel configuration: > >> > > >> > # Parallel port > >> > device=09=09ppc0=09at isa? irq 7 > >> > device=09=09ppbus=09=09# Parallel port bus (required) > >> > device=09=09lpt=09=09# Printer > >> > # > >> > # 2002 oct 27 - removed plip and added ppi. > >> > # > >> > #device=09=09plip=09=09# TCP/IP over parallel > >> > device=09=09ppi=09=09# Parallel port interface device > >> > #device=09=09vpo=09=09# Requires scbus and da > >> > > >> > any help would be very much appreciated > >> > > >> > > >> > To Unsubscribe: send mail to majordomo@FreeBSD.org > >> > with "unsubscribe freebsd-hackers" in the body of the message > >> > >> > >> > >> ----------------------------------------- > >> "UNIXMEXICO la comunidad *nix en todo M=E9xico!" > >> http://www.unixmexico.org/ > >> > >> > >> > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-hackers" in the body of the message > > > > ----------------------------------------- > "UNIXMEXICO la comunidad *nix en todo M=E9xico!" > http://www.unixmexico.org/ > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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